/******************************下雪特效*********************************/
@use "sass:math" as math;
@function random_range($min, $max) {
    $rand: random();
    $random_range: $min + floor($rand * (($max - $min) + 1));
    @return $random_range;
  }
  
  .snow {
    $total: 200;
    position: absolute;
    width: 10px;
    height: 10px;
    background: white;
    border-radius: 50%;
  
    @for $i from 1 through $total {
      $random-x: random(1000000) * 0.0001vw;
      $random-offset: random_range(-100000, 100000) * 0.0001vw;
      $random-x-end: $random-x + $random-offset;
      $random-x-end-yoyo: $random-x + math.div($random-offset, 2);
      $random-yoyo-time: math.div(random_range(30000, 80000),100000);
      $random-yoyo-y: $random-yoyo-time * 100vh;
      $random-scale: random(10000) * 0.0001;
      $fall-duration: random_range(10, 30) * 1s;
      $fall-delay: random(30) * -1s;
  
      &:nth-child(#{$i}) {
        opacity: random(10000) * 0.0001;
        transform: translate($random-x, -10px) scale($random-scale);
        animation: fall-#{$i} $fall-duration $fall-delay linear infinite;
      }
  
      @keyframes fall-#{$i} {
        #{percentage($random-yoyo-time)} {
          transform: translate($random-x-end, $random-yoyo-y) scale($random-scale);
        }
  
        to {
          transform: translate($random-x-end-yoyo, 100vh) scale($random-scale);
        }
      }
    }}